Re: Solaris hangs with 0.6.5?

[Cliff Skolnick <cl...@organic.com>]

OK..the sun guys are in serious bug crunch mode, and this is not an
official optimization.  I wonder if we can get a sunsite to run apache
and get the attention.  It will be a while :( before real time can be
spent on this...sigh...


On Mon, 26 Jun 1995 08:02:36 PDT, someone in sun wrote:

} 
} >  Here is your chance to see TCP problems in action on a solaris
} > box.  Ineterested in being involved with this?
} >
} 
} Only in an offline manner. [my manager] will kill me if I really spend time on
} this though it is more interesting. Ofcourse, thiswill need more
} investigating. 
} 
} Could this be going through PPP ? There is one bug
} where TCP exhibits this network over a large bandwidth-delay product networks
} including PPP over relatively slow lines. (bug 1175127 - RE brice). The
} workaround is to make tcp_rexmit_interval_min to 1000 (1000ms). I think
} PPP does a lot of buffering and the TCP RTT algorithm can only handle
} if RTT stays within mean+- 4sd and with buffering in PPP it strays beyond
} those bounds.
} 
} If it is not through PPP only, then it is "interesting". Ofcourse
} usual capturing with snoop when problem occurs and lookign at it
} using "snoop -V <src> <dst> | grep TCP" is where I would start
} if the blame is suspected on TCP. Trussing the application (truss -v all -f .
  .)
} to see if it is waiting on read/poll will also be a good thing to
} make sure that it is indeed waiting for more data that is not
} getting to it and would confirm that things are within the "expected"
} scenario with respect to suspected brokenness in TCP.
} 
} [ BTW, I had sent some notes on SO_LINGER to "cliffs@steam.com". THat was
} however not saying that it should be used. It would cause the server to
} block on that close() for a long time and you do not want that either
} (semantics over non-blocking sockets are broken in other interesting ways
} and I did not describe that. If they were not broken there, it would have
} almost been an interesting option to set ) ]